2018/12/16 by Miklós Laczkovich, Laczkovich, Miklos
Mathematics · #Functional Equations Stability Results #Mathematical and Theoretical Analysis #Advanced Banach Space Theory
paper · pdf · doi:10.48550/arxiv.1812.06434
Let G be a topological commutative semigroup with unit. We prove that a\ncontinuous function f colon G\→ cc is a generalized exponential polynomial\nif and only if there is an n\≥ 2 such that f(x1 +\… +xn ) is\ndecomposable; that is, if f(x1 +\… +xn )= sumik ui cd vi, where the\nfunction ui only depends on the variables belonging to a set emp \≠ Ei\n subsetneq x1 stb xn , and vi only depends on the variables\nbelonging to x1 stb xn se Ei (i=1 stb k).\n